This invention relates to a load retainer for use in a void of a cargo container, and more particularly, to a load retainer which can be locked into an expanded, generally symmetric load retaining configuration and/or converted into a collapsed storage configuration.
Shipment of products typically occurs using conventional rectangular cargo containers such as a truck trailer, railroad box car, the hold of a cargo ship and the like. Very often the cargo container is not entirely filled with the products being shipped. Furthermore, the cargo or load must be secured within the cargo container to prevent it from shifting during transportation and possibly damaging either the cargo or the cargo container.
Various techniques have been previously used to secure the load within the cargo container. These techniques include strategically arranging or organizing the cargo to minimize its straps, or tie-downs or nailing and otherwise securing boards between the cargo and the container. However, methods such as these have proven to be minimally effective and cannot be relied upon when there is a relatively large void in the cargo container.
The need to fill large volumes or voids has become particularly important due to the increased use of oversized truck trailers, rail cars, or the like. Problems associated with shifting cargo or loads are especially acute when relatively dense products are shipped. The dense products meet the weight limits of the cargo container while only filling up a relatively small fraction of available space therein. The failure to properly position the load and secure it within the trailer can result in illegal axle weight conditions, poor handling of the tractor trailer, rail car, cargo ship or the like, as well as an increased likelihood for damage to the cargo or the cargo container.
One prior solution to these problems is disclosed in U.S. Pat. No. 5,132,156 which is directed to a void filler constructed of a pair of panels which are connected at a hinge along the upper edge of the panels to form an inverted V-shaped structure. A limiter is attached at or near the lower edges of the panels to limit movement of the lower edges away from one another when the panels are in use and in the inverted V-shaped configuration. The device disclosed in U.S. Pat. No. 5,132,156 is positioned in the void of a cargo container between a container bulkhead and a load so that the upper and lower edges of that device are aligned between the load and the bulkhead. Specifically, the lower portion of the load is juxtaposed to the wider base region of the inverted V-shaped void filler whereas the upper portion of the load confronts the narrow point or upper region of the inverted V-shaped device. As a result of its configuration, loading between the upper and lower portions of that void filler is unsymmetric and the force generated by the tendency for the cargo to shift is not evenly distributed on the void filler. In particular, the force delivered to the upper narrow portion of the inverted V-shaped void filler is carried by a very small cross-sectional area of the void filler; namely, the upper point region. This loading condition becomes even more problematic when it is realized that a large portion of the force delivered by the load is in the upper portion of the load because the cargo has a tendency to tilt or tip over.
Therefore, one shortcoming of the void filler disclosed in U.S. Pat. No. 5,132,156 is that the majority of the force generated by the load is applied to the narrow portion of the device. Further, as a result of the force applied to the narrow portion of the void filler, the tendency for the void filler to collapse, tear, rip or be damaged is increased. Specifically, the hinge along the upper edge of the inverted V-shaped void filler may be torn or the bottom edges of the panels could be forced outwardly thereby ripping or tearing the limiter or the panels themselves.